As the UCLA-Caltech Medical Scientist Training Program (MSTP) approaches its 25th anniversary, its mission remains the same as it was when the Program was established in 1983: to promote the education of outstanding physician-scientists. To fulfill this mission, our current goals are to 1) recruit exceptionally bright and accomplished students who exhibit an unusual degree of passion for scientific knowledge and a life-long commitment to research and leadership, 2) help guide admitted students toward outstanding training environments that encourage individual thinking and provide students with the tools needed to develop into accomplished physician-scientists, 3) provide a comprehensive support system to meet the trainees'needs and 4) play an increasingly prominent role in guiding the career development of undergraduate students within the UCLA community, especially those from under-represented ethnic groups and disadvantaged backgrounds. To accomplish these goals as effectively as possible, the UCLA-Caltech MSTP is now run by two equal Co-Directors and two Associate Directors, all of whom are deeply committed to the Program. The Program is structured for an average of eight years of study. A new integrated, problem-based medical school curriculum is particularly well-suited for MSTP students, due to increased time for independent exploration and increased emphasis on research advances that contributed to current knowledge of disease etiology, diagnosis, and treatment. For their Ph.D. research, students choose mentors from a wide array of science and engineering Ph.D. Programs, with current students obtaining Ph.D.s in fields ranging from Philosophy to Policy Analysis. The MSTP's commitment to excellence was perhaps most apparent when UCLA and Caltech entered into an affiliation agreement ten years ago. This affiliation, which provides an opportunity for two students per year to perform their thesis research at Caltech, not only has increased the number of outstanding mentors available to students, but also appears to have increased the Program's visibility and recruitment success. The MSTP derives great benefit from recent dramatic improvements in physical facilities at both UCLA and Caltech, from the financial health of the universities, and from the recruitment of a large number of outstanding new faculty members to UCLA and Caltech and to UCLA's new California Nanosciences Institute and Institute for Stem Cell Biology and Medicine.